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Dynamic Seals

Dynamic seals are devices used to maintain a seal between moving or rotating parts. They are commonly used in areas such as hydraulic systems, pneumatic systems, engines and rotating equipment. The main function of dynamic seals is to prevent liquid, gas or other media from leaking from the connection and to prevent external impurities from entering.

Piston Seal

Pneumatic Piston Seal

Pneumatic piston seal is critical to the proper functioning of the cylinder. Piston seals prevent fluid from bypassing the piston, which would otherwise reduce the pressure differential across the piston, thereby reducing the force available to the cylinder to perform its work. There are generally two types of sealing elements commonly used in cylinders, one is a compression seal and the other is a pneumatic seal.

Rubber rotary water shaft seal 3

Rubber rotary water shaft seal

Rubber rotary water shaft seals are sealing devices designed to prevent liquid leakage around a rotating shaft. They form a seal interface, preventing liquid from entering or leaking through the contact between the shaft and the sealing lip. These seals are widely used in mechanical equipment, such as pumps, motors, engines, and industrial equipment. They are certified by ISO 9001, ISO/TS 16949, ASTM D2000, and REACH. They offer strong wear resistance, chemical resistance, high temperature resistance, and weather resistance. They are simple to install, require less maintenance, and are cost-effective.

Dynamism Seal

A dynamic seal is a component that is frequently found in mechanical and industrial equipment that stops liquids or gasses from leaking. They are made to effectively seal during movement to stop media leaks.

Mostly utilized on revolving or reciprocating parts like shafts, pistons, and valves, dynamic seals They typically have strong resistance to wear and corrosion and are composed of elastic materials, like rubber or polymer. Dynamic seals must adjust to shifting components without compromising sealing efficiency.

 

1.Common types of dynamic seals

Seals, piston seals, shaft seals, etc.

The sealing ring is one of the most commonly used dynamic seals. It usually adopts a circular ring shape and is used to prevent liquid or gas from leaking through the axial direction. Piston seals are used to prevent medium leakage between the piston and the cylinder. Common types include piston rings and piston rod seals. Shaft seals are used to protect the seal between the rotating shaft and the external environment to prevent the leakage of lubricating oil or other media.

 

Dynamic seal selection depends on the application’s operating conditions and requirements. Because different working environments and media may have different effects on seals, such as high temperature, high pressure, chemical corrosion, etc. Therefore, when selecting dynamic seals, factors such as material tolerance, sealing effect, friction loss, etc. need to be considered.

 

2.Applicable working environments and media

Some dynamic seals can work in high temperature environments. For example, high temperature oil seals are commonly used in hydraulic systems and engines.

Some dynamic seals made of special materials can work in low-temperature environments, such as liquid nitrogen seals used in low-temperature liquid nitrogen storage and delivery systems.

Dynamic seals cope with high-pressure media, such as those used in high-pressure pumps or compressors.

For corrosive media, choose seals made of corrosion-resistant materials, such as polytetrafluoroethylene sealing rings, which are widely used in the chemical industry.

Dynamic seals are required to provide effective sealing on high-speed rotating components, such as shaft seals in wind turbines.

Dynamic seals are also used in the food and pharmaceutical industries.

 

3.What are the suitable rubber materials? (NBR,SBR,FKM,ACM,CR,EPDM)

Nitrile rubber (NBR)

Nitrile rubber has excellent oil resistance and wear resistance and is widely used in dynamic seals, especially for sealing media such as lubricating oil and fuel.

 

Styrene-butadiene rubber (SBR)

Styrene-butadiene rubber has good oil resistance and wear resistance, and is suitable for dynamic seals under some special working conditions, such as sealing of high-speed rotating parts.

 

Fluorine rubber (FKM)

Fluorine rubber has excellent high temperature resistance and corrosion resistance, and is widely used in dynamic seals in harsh environments such as high temperature and chemical corrosion.

 

Acrylic rubber (ACM)

Propylene rubber has good heat resistance and oil resistance, and is suitable for dynamic seals in high temperature and lubricating oil environments.

 

Neoprene (CR)

Neoprene has good oil resistance, chemical resistance and aging resistance, and is suitable for dynamic seals under some special working conditions.

 

Ethylene propylene rubber (EPDM)

Ethylene propylene rubber has good heat resistance, weather resistance and corrosion resistance, and is suitable for dynamic seals in some high temperature and outdoor environments.

 

4.What are the mechanical properties?

(Sealing, wear resistance, heat resistance, elastic recovery, resistance to compression deformation, friction characteristics…)

The main purpose of dynamic seals is to provide an effective seal against leakage of liquid or gas. Therefore, good sealing performance is one of its most important mechanical properties. Sealing performance is usually measured by leakage rate, sealing pressure, sealing performance durability and other indicators. Its sealing performance is usually measured by leakage rate, sealing pressure, sealing performance durability and other indicators.

 

Wear resistance

Dynamic seals need to be in contact with moving parts when in motion, so their wear resistance is an important mechanical performance indicator. The wear resistance directly affects the service life and performance stability of the seal.

 

Heat resistance

In some applications, dynamic seals may be exposed to high temperatures, so their heat resistance is a key mechanical performance indicator. The quality of heat resistance affects the stability and sealing effect of seals in high temperature environments.

 

Elastic recovery

Dynamic seals should be able to return to their original shape and size after being deformed or stressed. Elastic recovery is one of the important mechanical properties to ensure the normal operation of seals.

 

Resistance to compression deformation

Dynamic seals should be able to maintain good shape stability and not undergo excessive compression deformation when subjected to pressure. The resistance to compression deformation is directly related to the sealing effect and service life of the seal.

 

Friction characteristics

The friction characteristics between dynamic seals and moving parts have a significant impact on their performance and service life. Proper friction characteristics can provide good sealing effect and movement performance.

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